## cli.summary()


What a report's contract means for the data, in words:


Usage

``` python
cli.summary(
    report,
    sources=None,
)
```


- `guarantees`: what every output row (or the output) meets, proved;
- [checks](io.Contract.md#sverify.io.Contract.checks): what each refresh checks on the data before it writes (the preconditions on the sources, postconditions checked on the output, sums assumed to fit). With `sources`, only the preconditions on those tables: the others follow from what the transforms feeding them guarantee;
- `not_proved`: what is not proved, and the runtime errors it may raise.